WARNING  Batteries can emit explosive gases. To reduce the possibility of personal injury, always ventilate the compartment before servicing the batteries. To reduce the possibility of arcing, remove the negative (-) battery cable first and attach the negative (-) battery cable last.

WARNING  Coolant is toxic. Keep away from children and pets. If not reused, dispose of in accordance with local environmental regulations.

• Disconnect the batteries. Refer to the OEM service manual.
• Drain the engine coolant. Refer to Procedure 008-018 in Section 8.
• Remove the fuel pump. Refer to Procedure 005-016 in Section 5.
• Remove the air compressor coolant lines. Refer to Procedure 012-004 in Section 12.

NOTE: The illustrations shown will be of the SS model single cylinder air compressor. Differences in procedures for SS, QE, and ST model Cummins® air compressors will be illustrated where necessary.

Remove the air connections from the air compressor.

Remove the air compressor support bracket and capscrews.

Remove the four capscrews, the air compressor, and splined coupling.

Inspect the compressor housing for cracks or other damage.

Inspect the splined coupling for cracks or other damage.

NOTE: It is not necessary to time the air compressor on the NT engine. Although the Big Cam III through 88NT publications have specified air compressor timing, this is not required on any NT engine.

Position the timing mark on the air compressor crankshaft at the 12-o'clock position.

Position the accessory driveshaft dowel pin at the 2-o'clock position as view from the front of the engine.

Install the splined coupling onto the accessory drive shaft.

Make sure the gasket surfaces of the accessory drive and the air compressor are clean and not damaged.

Use a new gasket and install the air compressor and four capscrews to the accessory drive.

Install the air compressor support bracket.

Tighten the capscrews.

NOTE: If rubber grommets are used on the coolant lines, make sure they are installed carefully to prevent cuts or tears to the grommets which will cause coolant leaks. When flexible tubing is used, make sure that it does not rub any other surfaces.

Install the coolant and air lines to the air compressor and tighten.

Install the fuel pump drive coupling onto the air compressor.

WARNING  Batteries can emit explosive gases. To reduce the possibility of personal injury, always ventilate the compartment before servicing the batteries. To reduce the possibility of arcing, remove the negative (-) battery cable first and attach the negative (-) battery cable last.

WARNING  Coolant is toxic. Keep away from children and pets. If not reused, dispose of in accordance with local environmental regulations.

• Install the air compressor coolant lines. Refer to Procedure 012-004 in Section 12.
• Install the fuel pump. Refer to Procedure 005-016 in Section 5.
• Fill the engine cooling system. Refer to Procedure 008-018 in Section 8.
• Connect the batteries. Refer to the OEM service manual.